STUDY OBJECTIVE:Point-of-care testing reduces time to cardiac marker results in patients evaluated for acute coronary syndromes, yet evidence this translates to a decreased length of stay is lacking. We hypothesized that point-of-care testing decreases length of stay in patients being evaluated for acute coronary syndromes in the emergency department (ED). METHODS:Patients being evaluated for possible acute coronary syndromes at 4 EDs in the United States were randomized to having point-of-care markers as well as central laboratory markers, or central laboratory markers only (laboratory arm). Point-of-care markers were obtained using early serial testing at presentation and at 90, 180, and 360 minutes as required by the treating physician. Evaluation, treatment, and disposition decisions were at the treating physician's discretion. Length of stay was from presentation to the time of departure from the ED, either to an inpatient setting or to home. RESULTS:There were 1,000 patients in each study arm. There were 520 patients discharged home from the ED. Median (interquartile range) time to discharge home was 4.6 hours (3.5 to 6.1 hours) in laboratory patients and 4.5 hours (3.5 to 6.1 hours) in point-of-care patients. Median (interquartile range) time to transfer to an inpatient setting for admitted patients was 5.5 hours (4.2 to 7.5 hours) in laboratory patients, and 5.4 hours (4.1 to 7.3 hours) in point-of-care patients. At one site, time to transfer to the floor was reduced in the point-of-care arm compared with the laboratory arm (difference in medians 0.45 hours; 95% confidence interval [CI] -0.14 to 1.04 hours). At one site, time to ED departure for discharged patients was higher in the point-of-care arm than the laboratory arm (difference in medians 1.25 hours; 95% CI 0.13 to 2.36 hours). CONCLUSION:The effect of point-of-care testing on length of stay in the ED varies between settings. At one site, point-of-care testing decreased time to admission, whereas at another, point-of-care testing increased time to discharge. Potential effects of point-of-care testing on patient throughput should be considered in the full context of ED operations.